Seat, couch or bed, provided with at least one vacuum cushion

ABSTRACT

This invention relates to a seat, couch or bed, provided with at least one vacuum cushion comprising an air-tight flexible envelope containing a coherent porous mass or resiliently compressible intercommunicating open cellular material, having an inherent rigidity capable of substantially supporting the weight of an occupant without collapsing , a vacuum source, pipes for connecting the interior of this envelope with said vacuum source and with an ambient environment, at least one valve for selectively opening or for shutting off these communications with the envelope, in order to control the thickness of the cushion independently of the occupant&#39;&#39;s weight, and for the purpose of directing the compression of the porous mass in the direction of its thickness and facilitating the evacuation of the air contained in the cells of the porous mass when the envelope is in communication with the vacuum source, an additional air-permeable layer which allows, whatever stress is exerted on this additional layer, the circulation of air through same, between the porous layer and the pipe of the valve communicating with the vacuum source, this pipe discharging into this additional layer, said additional layer being provided in the envelop on that face of the porous mass opposite the face on which the occupant&#39;&#39;s weight is applied.

United States Patent 1 Braun 1 May 1, 1973 SEAT, COUCH OR BED, PROVIDED WITH AT LEAST ONE VACUUM CUSHION [75] Inventor: Francois Marie Kraainem, Belgium Joseph Braun,

[73] Assignee: Societe anonyme belge d. Exploitation de la Navigation aerienne (Sabena), Brussels, Belgium Primary ExaminerCasmir Av Nunberg Att0rneySughrue, Rothwell, Mion, Zinn & Macpeak 5 7] ABSTRACT This invention relates to a seat, couch or bed, provided with at least one vacuum cushion comprising an air-tight flexible envelope containing a coherent porous mass or resiliently compressible intercommunicating open cellular material, having an inherent rigidity capable of substantially supporting the weight of an occupant without collapsing a vacuum source, pipes for connecting the interior of this envelope with said vacuum source and with an ambient environment, at least one valve for selectively opening or for shutting off these communications with the envelope, in order to control the thickness of the cushion independently of the occupants weight, and for the purpose of directing the compression of the porous mass in the direction of its thickness and facilitating the evacuation of the air contained in the cells of the porous mass when the envelope is in communication with the vacuum source, an additional air-permeable layer which allows, whatever stress is exerted on this additional layer, the circulation of air through same, between the porous layer and the pipe of the valve communicating with the vacuum source, this pipe discharging into this additional layer, said additional layer being provided in the envelop on that face of the porous mass opposite the face on which the occupants weight is applied.

13 Claims, 4 Drawing Figures PATENTED 713 7 4 3,730,588

SHEET 1 (IF 2 SEAT, COUCH OR BEID, PROVIDED WITH AT LEAST ONE VACUUM CUSHION DESCRIPTION ble of substantially supporting the weight of an occul0 pant without collapsing, a vacuum source, pipes for connecting the interior of this envelope with said vacuum source and with an ambient environment, at least one valve for selectively opening or for shutting off these communications with the envelop, in order to control the thickness of the cushion independently of the occupants weight.

In seats, couches or beds of the above-mentioned type it has been found that when the valve vents the envelop of the cushion to the vacuum source, the cellular material tends to be compressed in all directions thus collapsing the cells situated in the vicinity of the inlet pipe before the air contained in its cells farthest from the pipe are evacuated.

The object of the invention is to improve the cushion of the type mentioned above, making it possible to direct the compression of the porous mass essentially in the direction of its thickness and likewise enabling the evacuation of the air contained in its cells farthest from the air pipe when the envelope is in communication with the vacuum source.

According to the invention there is provided in the envelope on that face of the porous mass opposite the face on which the exterior occupants weight is to be applied, an additional air-permeable layer which allows, whatever stress is exerted on this additional layer,

the circulation of air through same between the porous layer and the air pipe to the valve controlling communication with the vacuum source, this pipe discharging into said additional layer.

This additional layer also prevents the porous mass from being sucked into the pipe connected to the valve.

In accordance with another feature of the invention the additional layer extends over part of that face of the cellular porous material opposite the face on which the load is to be applied, so that the cells situated in the porous mass, facing this additional layer, are more exhausted of air and compressed by the sucking action from the vacuum source than the cells of the other parts of the porous mass. Consequently there is formed in the cushion a local impression substantially limited by the surface of the additional layer.

In accordance with a feature of the invention the additional air-permeable layer is constituted by a mesh According to another feature the mass of porous material is provided with flat flexible reinforcements forming frames, which are inserted into its thickness in the vicinity of its periphery, in a plane substantially perpendicular to the thickness of the cushion.

By these various means the cushion, when under suction, can be compressed only in the direction of its thickness.

Other features and details of the invention will appear in the course of the description of the drawings attached to this specification, which represent diagrammatically and solely by way of example one form of embodiment of the invention.

FIG. 1 is a diagrammatic side view on a reduced scale of a seat according to the invention;

FIG. 2 is a side view of a vertical section through the cushion forming the back;

FIG. 3 is a rear view of the back;

FIG. 4 is a side view of a section through the cushion used as a seat.

in those drawings the same reference numerals designate like parts.

In FIG. 1 there is shown a seat 1 whose rigid frame 2 is hollow and airtight so as to form a reservoir in which a vacuum can be created, for example by means of a vacuum pump 29 in such a way that this reservoir can constitute a vacuum source. This structure has two cushions 3, one of which serves as the back 4 and the other as the seat 5.

Each cushion 3 comprises a flexible airtight envelope 6 containing resiliently compressible porous cellular material 7, but of a rigidity sufficient to withstand the compression resulting from the occupants weight alone. When the interior of the envelope is put into communication with the vacuum source, the cells of this porous mass collapse due to their being more or less exhausted of air.

Advantageously the cellular porous material consists of polyether or polyurethane foam. This porous material is provided in the form of a coherent mass cut or moulded to a curved shape advantageous for the comfort of the user of the seat.

In the example represented this cushion only extends as a seat at the front part of the seat but it could naturally extend over the entire surface of the seat. It could 1 likewise constitute a mattress to equip a bed.

Each cushion 3 comprises means such as a three-way valve 8 for temporily connecting the interior of the envelope on the one hand' with the ambient atmosphere through the pipes 9 and- 10, and on the other hand with the suction source constituted by the reservoir 2 through the pipes 9 and 11. In the example represented, the air-tight reservoir formed by the hollow frame 2 of the seat is connected to the vacuum pump 29 by a pipe 13 in which there is inserted a nonreturn valve 30 which opens in the direction of the arrow.

By means of the valve 8 it is possible to control the pressure inside the envelope and to thus modify the degree of compression of the porous cellular material so as to adapt it to the anatomy of the occupant of the seat, irrespective of his weight. More particularly where the cushion is used as a seat, it is possible therefore to adjust its height to the size of the occupant. When the pressure inside the envelope is restored, the latter takes up its normal expanded form under the ac tion of the internal force of the porous mass which had been previously collapsed under suction.

With the purpose of the directing of the compression of the porous cellular mass in the direction of its thickness and facilitating the evacuation of the air contained in the cells of this mass when the envelope is in communication with vacuum source, there is provided in accordance with the invention in the envelope 6, on the face of the porous material opposite'that on which the load is applied, an additional layer of coherent material 15.

This additional layer allows air to pass through it whatever stress is exerted on it by the porous mass under the effect of the exterior load and/or suction. This layer is advantageously provided in the form of meshes extending three-dimensionally.

It has been found surprising moreover that by the presence on one part only of the face of the porous mass opposite that on which the weight of the occupant is applied, of an additional air-permeable layer, it is possible to create in this part of the porous mass a greater and quicker exhaust of air than in the parts adjacent this porous mass. There is produced a limited local impression on the surface of the additional layer, due to a more substantial squeezing of the cells in this part of the porous mass situated facing the additional layer, than in its adjacent parts. Furthermore this porous mass adapts to the shape of the part of the user in contact with the cushion.

in the case where the cushion is used as the back, as shown in FIG. 3, the additional layer is cut out substantially in the shape of an X, i.e. substantially in the shape of two superposed trapezia touching one another at their short base.

Under the action of suction there is likewise produced here amore substantial squeezing of the cells in the porous coherent mass situated opposite the additional layer, than in the adjacent parts 16-17, so that these latter remain projecting in relation to the part situated between them, thus ensuring an enveloping form for the back of the person using the seat.

When the cushion is used as a seat, as shown in FIG. 4, the meshed additional layer extends over all the face 18 of the coherent mass of porous material opposite the face 19 on which the load is applied.

In the form of embodiment represented in the drawings, the addidional layer of coherent,- meshed material is formed by a reticulated foam of polyurethane. 1

This additional layer could likewise be formed by an agglomeration of textile filaments, of rubber or of metal having points where they adhere to one another or join one another.

The reticulated foam has however the advantage over the other materials of being light, of being able to be easily compressed resiliently, of being able to be cut accordingly to the shape desired and of being able to be moulded with the porous mass.

The cushion face opposite that on which the weight is applied is reinforced by a rigid plate 20 which has edges 21 forming a retainer for the additional layer, while the coherent mass of porous material is strengthened with flat flexible reinforcements forming frames and which are inserted in marginal slots 23 provided in the thickness of this mass, in the vicinity of its periphery in a plane substantially perpendicular to the thickness of the cushion. Since these reinforcements are accommodated in marginal slots in the thickness of the porous mass they are imperceptible to the user of the seat. These means likewise ensure, during squeezing of the porous mass under the effect of suction that the cushion can only be compressed in thickness.

In another form of embodiment not shown, the reinforcements are incorporated in the porous coherent mass during the moulding of this mass.

Advantageously the rigid plate 20 constitutes one face of the air-tight envelope 6 opposite that to which the weight is applied. The envelope 6 is provided with flanged edges 24-25 which are fixed by welding or adhesive to the corresponding edges of the rigid plate 20 which likewise has raised edges 21 directed towards the interior of the cushion forming supplementary surfaces of adhesion for the envelope and forming a retainer for the additional layer.

In another form of embodiment not shown, the coherent porous mass and the additional layer mentioned above have externally a fluidtight surface constituting said air-tight envelope. The fluidtightness is obtained in this case for example, either during the moulding of the coherent mass and of the additional layer, or by the application of a layer of fluidtight lining material such as liquid latex applied by dipping or spraying.

Furthermore with a view to ensuring a circulation of air between the occupant and the airtight envelope of the cushions, there is arranged between the upholstery 26 of the seat and the envelope 6, at least at the places where the weight is applied, a layer of flexible polyurethane foam 27 formed as a reticulated network.

In the example shown in FIG. 1 this layer of reticulated foam extends on one hand over the entire extent of the back, and on the other hand over the whole seating surface, one part of which is formed by one of the vacuum cushions and the other part by a conventional cushion.

A safety valve 28 which opens in the direction of the arrow to the ambient atmosphere when the pressure of same is lower than the internal pressure of the cushion, is provided in the pipe circuit 9.

What is claimed is: I

l. A seat, couch or bed, provided with at least one vacuum cushion comprising an airtight flexible envelope; a porous layer means within said envelope, said porous layer means comprising a coherent porous mass or resiliently compressible intercommunicating open cellular material, having an inherent rigidity capable of substantially supporting the weight of an occupant without collapsing; a vacuum source; pipes for connecting the interior of said envelope with said vacuum source and with an ambient environment; at least one valve for selectively opening and closing communications with said envelope, to control the thickness of the cushion independently of the weight of the occupant; and additional air-permeable layer means for directing the compression of the porous layer means in the direction of its thickness and facilitating the evacuation of the air contained in the cells of the porous layer means when the envelope is in communication with the vacuum'source, wherein said additional layer means is positioned between the porous layer means and the pipe of the valve communicating with the vacuum source, said pipe discharging into said additional layer means, and wherein said additional layer means is within the envelope on the face of the porous layer means opposite the face on which the occupants weight is applied.

2. A seat, couch or bed, as claimed in claim 1, wherein the additional layer means extends over only one part of the face of the porous layer means opposite that to which the occupants weight is applied, whereby the cells of said porous layer means, facing the additional layer, are more exhausted of air under the effect of suction than the cells of the other parts of the porous layer means in the cushion, whereby there is formed an impression substantially limited by the surface of the additional layer means.

3. A seat, couch or bed, as claimed in claim 2, wherein the cushion serves as a back, and wherein the additional layer means extends substantially in the form of two superposed trapezoids touching one another at their short base.

4. A seat, couch or bed, as claimed in claim 1, wherein the additional layer means comprises a three dimensional mesh network.

5. A seat, couch or bed, as claimed in claim 1, wherein the additional layer means comprises a reticulated foam.

6. A seat, couch or bed as claimed in claim 1, wherein the additional layer means comprises an agglomeration of filaments which are permeable to air, having points where they adhere to one another or join one another.

7. A seat, couch or bed as claimed in claim 1, wherein the additional layer means is resiliently compressible.

8. A seat, couch or bed as claimed in claim 1, wherein the face of the cushion opposed to that on which the weight is applied is reinforced by a rigid plate.

9. A seat, couch or bed as claimed in claim 7, wherein the rigid reinforcing plate comprises the face of the airtight envelope opposite that on which the weight is applied.

10. A seat, couch or bed as claimed in claim 9, wherein the rigid plate has projecting edges directed towards the interior of the cushion so as to form a retainer for accommodating the additional layer and surfaces for adhering to the flexible envelope.

11. A seat, couch or bed as claimed in claim 1, wherein said porous layer means includes flat flexible reinforcement means for forming frames within said porous mass in the vicinity of its periphery, in a plane substantially perpendicular to the thickness of the cushion.

12. A seat, couch or bed as claimed in claim 11, wherein the reinforcement means are incorporated in the cellular porous mass during its formation by moldmg.

13. A seat, couch or bed as claimed in claim 1, wherein the porous layer means and the additional layer means to which it is joined are provided externally with a fluidtight surface constituting the airtight envelope. 

1. A seat, couch or bed, provided with at least one vacuum cushion comprising an airtight flexible envelope; a porous layer means within said envelope, said porous layer means comprising a coherent porous mass or resiliently compressible intercommunicating open cellular material, having an inherent rigidity capable of substantially supporting the weight of an occupant without collapsing; a vacuum source; pipes for connecting the interior of said envelope with said vacuum source and with an ambient environment; at least one valve for selectively opening and closing communications with said envelope, to control the thickness of the cushion independently of the weight of the occupant; and additional air-permeable layer means for directing the compression of the porous layer means in the direction of its thickness and facilitating the evacuation of the air contained in the cells of the porous layer means when the envelope is in communication with the vacuum source, wherein said additional layer means is positioned between the porous layer means and the pipe of the valve communicating with the vacuum source, said pipe discharging into said additional layer means, and wherein said additional layer means is within the envelope on the face of the porous layer means opposite the face on which the occupant''s weight is applied.
 2. A seat, couch or bed, as claimed in claim 1, wherein the additional layer means extends over only one part of the face of the porous layer means opposite that to which the occupant''s weight is applied, whereby the cells of said porous layer means, facing the additional layer, are more exhausted of air under the effect of suction than the cells of the other parts of the porous layer means in the cushion, whereby there is formed an impression substantially limited by the surface of the additional layer means.
 3. A seat, couch or bed, as claimed in claim 2, wherein the cushion serves as a back, and wherein the additional layer means extends substantially in the form of two superposed trapezoids touching one another at their short base.
 4. A seat, couch or bed, as claimed in claim 1, wherein the additional layer means comprisEs a three dimensional mesh network.
 5. A seat, couch or bed, as claimed in claim 1, wherein the additional layer means comprises a reticulated foam.
 6. A seat, couch or bed as claimed in claim 1, wherein the additional layer means comprises an agglomeration of filaments which are permeable to air, having points where they adhere to one another or join one another.
 7. A seat, couch or bed as claimed in claim 1, wherein the additional layer means is resiliently compressible.
 8. A seat, couch or bed as claimed in claim 1, wherein the face of the cushion opposed to that on which the weight is applied is reinforced by a rigid plate.
 9. A seat, couch or bed as claimed in claim 7, wherein the rigid reinforcing plate comprises the face of the airtight envelope opposite that on which the weight is applied.
 10. A seat, couch or bed as claimed in claim 9, wherein the rigid plate has projecting edges directed towards the interior of the cushion so as to form a retainer for accommodating the additional layer and surfaces for adhering to the flexible envelope.
 11. A seat, couch or bed as claimed in claim 1, wherein said porous layer means includes flat flexible reinforcement means for forming frames within said porous mass in the vicinity of its periphery, in a plane substantially perpendicular to the thickness of the cushion.
 12. A seat, couch or bed as claimed in claim 11, wherein the reinforcement means are incorporated in the cellular porous mass during its formation by molding.
 13. A seat, couch or bed as claimed in claim 1, wherein the porous layer means and the additional layer means to which it is joined are provided externally with a fluidtight surface constituting the airtight envelope. 